Process of modifying vinyl resins



Patented Aug. 8, 1933 v v UNITED STATES PATENT orrics PROCESS OF MODIFYING VINYL RESINS Foster Robertson, Pittsburgh, Pa., assignor to Carbide and Carbon Chemicals Corporation, a Corporation of New York No Drawing. Application September 11, 1930 Serial No. 481,339

4 Claims. (Cl. 260-2) Many vinyl compounds can be caused to polyliquids and the like in the presence of alkaline merize and form resins. The polymerization is substances. conveniently carried out by dissolving the vinyl The invention may take many different forms compound in an appropriate solvent, and then with respect to the vinyl compound polymerized,

5 heating the solution, or subjecting it to ultrathe solvent in which the polymerization is carviolet radiation, or catalyzing the polymerization ried out, the concentration of the resulting resin with one of the many substances, for example solution, the precipitant used to throw down the benzoyl peroxide, known to be effective for this resin, and the alkaline substance used to modify purpose. The vinyl compound used in making the resin. In general, the resins made by the 1c the resin may be one of the easily-prepared esters, conjoint polymerization of two or more vinyl such as vinyl acetate or vinyl chloride. Among compounds, and particularly the chloride and the many suitable solvents in which the polyacetate, are most useful when modifiedinaccordmerization may be conducted are toluene and ance with the present invention. The resins are acetone. The resin can be recovered in solid most completely changed, that is, their solubility 15 form by evaporating the solvent, or a concenand iusibility are most diminished, whenthey trated solution-may be made by evaporating a are precipitated under strongly alkaline condipart of the solvent. To such concentrated solutions, and if a very high-melting material is detion there may be added appropriate diluents sired, we prefer to use such strong bases as the which do not precipitate the resin, thus proalkali metal hydroxides. Using ethyl alcohol as 20 ducing a lacquer base, the precipitant, about 0.5% to 1.0% of caustic The various vinyl resins have certain properties soda (based on the resin) W n y as s give in common, but differ specifically depending upresins which are still soluble, but which are imon the vinyl compounds from which they are proved because of their raised softening points, made, and upon other circumstances. Thus vinyl while 3% to 10% of caustic soda will, under many 25 acetate gives a resin having good adhesive and conditions, yield resins which are practically incohesive properties, and being comparatively soluble in toluene and other solvents, but which readily'soluble and fusible. Vinyl chloride forms are nevertheless very us as oplastic a resin which is harder, less soluble, and less substances. With resins produced by the confusible, but which tends to be friable. By conj int p y at of vinyl acetate a d v y 30 jointly polymerizing (by hi h i nt polychloride, less alkali is required to destroy the merizing in mutual contact) mixtures of vinyl solubility as the proportion of the chloride in chloride and vinyl acetate, resins of particulafly the original mixture increases. The alkali metal valuable properties are formed. These resins hydroxides may be replaced with many other give excellent lacquers, and are also useful in alkaline substances, for eXample o a, sodi- 35 thermoplastic and other compositions, It i um carbonate, ethanolamines, and other amines. noteworthy that resins identical with those pre- Such weaker bases act more slowly, or produce pared by conjoint polymerization cannot be made s d ficatio 0f the resin.

by separately polymerizing the single vinylcom- The invention is further illustrated by the pounds, and thereafter mixing the products so f win sp ifi amp so obt ined Five hundred pounds of an acetone solution After a vinyl compound is polymerized in solucontaining 250 pounds of vinyl resin is added tion, the resin may be precipitated by diluting slowly to 250 pounds of a mixture containing the solution with an appropriate substance, for equal parts by volume of ethyl and isoprop l example methyl, ethyl or isopropyl alcohol, or hol together with 1.0% of caustic soda. The

45 mixtures of alcohols, or mixtures of alcohols with mixture is stirred vigorously and 500 pounds of water. The properties of the resin do not appear water is added. The resin is separated from the to be much affected by precipitating it in this liquid by filtration through a cloth, and is thorfashion. If collected and dried, it exhibits about oughly washed with water. The resin is then the same solubility and fusibility as if it had been spread on pans and dried in an air oven, recovered in solid form by evaporating the solvent I claim:-- in which it was produced. 1. Process of diminishing the fusibility and sol- The present invention comprises a process ubility of a polymerized vinyl ester resin which w y Vinyl resins may be rendered less solucomprises precipitating the resin from solution ble a u and it comprises the p eoipitaand subjecting it at the moment of precipitation 55 tion of the resins from solution by alcoholic to the action of a quantity of a water-soluble basic compound insufiident to cause appreciable hydrolysis of said. resin under the conditions of precipitation.

g Process Qf 1' w :1; the fusibility and solubiiity of o polymerized vinyl ester resin which comprises precipitating the resin from solution with a. quantity of an alkaline alcoholic compound insuflioient to hydrolyze appreciably said resin under the conditions of precipitation.

3. Process of diminishing the fusibility and soiubility of a. resin produced by the conjoint polymerization of vinyl ecetete end vinyl cmoride, which comprises precipitating the resin from so- 

